Kugisho MXY7 Ohka 櫻花 Model 22 and the Campini Jet

WW II’s combat operations had ended in the European theater but was continuing in earnest in the Pacific theater. The invasion of Japan by the Allies, mostly by United States and British forces, was inevitable as well as imminent. The Japanese government and military forces had long since realized the war would not be won by them but they continued to fight. Japanese combat personnel now fighting to protect their way of life, fearing its loss more than life itself. Controlling factions in the government strategically planning for their citizens to be exploited and certainly sacrificed in future combat operations. Imperial Japanese Naval (IJN) aviators had been flying Tokko独鈷 (Special Attack), kamikaze, missions for some time. Although popularized by the command structure as pilots eagerly willing to sacrifice themselves, the reality was they were solemnly and dutifully protecting their families — pragmatically there was little chance of returning from a combat mission due to overwhelming odds as well as their lack of training, so many saw this as a way to have the cost of their lives worth something instead of simply perishing.

The Ohka 櫻花 was developed as a flying bomb, quite literally it was a bomb with wings and a trio of rocket motors. It suffered from short range and most of these missions failed when the mother ships (Mitsibishi G4M “Betty” bombers) were destroyed in the air. The Model 22 was designed to extend the range from a 23 miles (37km) to 81 miles (130km), in part by halving the warload to a 1300 pounds (600kg) as well as a different engine. The range was likely estimated since I do not believe a Model 22 was flown and certainly not on a combat mission.

It is the engine that makes this Ohka 櫻花 unique as it is a Campini jet design. Originally this engine was categorized as a thermojet but that term has evolved to a different meaning. It is now categorized as a motorjet with the concept being a simple one. This aircraft was powered by a Ishikawajima Tsu-11 which consisted of an in-line four cylinder reciprocating engine whereby the exhaust drove a compressor blade fan with the generated thrust augmented by what is tantamount to an afterburner. The piston engine would be started and left in idle during flight with the mother ship and at the proper time the pilot would release from the mother ship and accelerate the engine.

The air inlets for the reciprocating engine of the Campini jet design — photo by Joseph May

Low frontal area of the Ohka — photo by Joseph May

The Ohka’s size as compared to conventional aircraft — photo by Joseph May

Kugisho MXY7 Ohka 櫻花 Model 22 — photo by Joseph May

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神風 Kamikaze Images is an academia quality web site focused on the Kamikaze forces Japan trained and fielded, along with memorials by families and villages as well as museums. It is written by Bill Gordon who continues to research as visit sites in Japan in his continuing efforts.